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Biomedical subjects

G Kawasaki

Publications and source records attributed to G Kawasaki.

10 recordsLinked to original sources
PubMed1995

Ultrastructural and biochemical studies of the effect of polychlorinated biphenyl on mouse parotid gland cells.

These effects of polychlorinated biphenyl (PCB) were examined by light and electron microscopy and biochemical analysis of lysosomal enzyme activities. Several experimental protocols with dosage schedules of either 0.2, 2.0, or 20 mg/kg of PCB were used. Typical histological changes were observed in mice given 2 mg/kg of PCB in a single injection. There were no remarkable changes until 4 days after PCB administration; marked cytoplasmic vacuolation was observed in parotid acinar cells at 7 days. The activities of lysosomal enzymes increased after the PCB injection and their maximum values appeared consistently at 4 days after the treatment; the increases were threefold for acid phosphatase, twofold for beta-glucuronidase, threefold for cathepsin D, fivefold for cathepsin H and twofold for cathepsin L. As vacuolation was preceded by a large increase in lysosomal enzyme activities and the vacuoles co-localized with lysosomes, it is suggested that an increase in these activities induced by PCB may be closely related to the development of vacuolation in the parotid acinar cells as a subacute effect of PCB.

Alkaline Phosphatase↗
PubMed1994

Induction of drug metabolizing enzymes by polychlorinated biphenyl in the parotid gland and relation to changes in vitamin A content and morphological changes.

The relationship between the morphological changes and vitamin A content during the development of acute toxicity induced by polychlorinated biphenyl (PCB) in mouse parotid glands was investigated. PCB was administered intraperitoneally at a single dose of 2 mg/kg. Ultrastructural studies revealed remarkable morphological changes in the rough endoplasmic reticulum, nucleus, Golgi apparatus and the secretory granules at 7 days after the administration of PCB. The activities of adenosine monophosphatase (AMPase) and alkaline phosphatase were increased 1 day after PCB administration. Then the activity of NADPH-cytochrome c reductase increased 4 days after PCB administration. Subsequently, the vitamin A content of the parotid glands significantly decreased at 7 days compared with the control. These sequential changes in enzyme activities implied that the decrease of vitamin A content in the parotid glands may be partly due to catabolism of vitamin A by increased activities of microsomal enzymes induced by PCB. In conclusion, it is suggested that PCB also induces drug metabolizing enzymes in the parotid gland cells and that the acute toxicity of PCB on this tissue may occur, at least partly, through the reduction of vitamin A not only by the secondary effect from liver impairment but also by the locally accelerated catabolism of vitamin A in the mouse parotid gland.

Animals↗
PubMed1987

Augmentation of lung antineutrophil elastase capacity with recombinant human alpha-1-antitrypsin.

To evaluate the potential use of recombinant DNA-produced alpha-1-antitrypsin (alpha-1-AT) to augment the lung antineutrophil elastase defenses in alpha-1-AT deficiency, we compared the kinetics of intravenously administered recombinant produced alpha-1-AT (r alpha-1-AT) and purified normal human plasma alpha-1-AT (p alpha-1-AT) in the blood and lung of rhesus monkeys. The r alpha-1-AT was produced in yeast transformed with an expressing plasmid containing a full-length human alpha-1-AT complementary deoxyribonucleic acid and purified to greater than 99% homogeneity. The r alpha-1-AT has a molecular weight of 45,000, no carbohydrates, and is identical in sequence to normal plasma alpha-1-AT except for an additional N-terminal acetylmethionine. Despite its lack of carbohydrates, the r alpha-1-AT inhibited human neutrophil elastase with an association rate constant similar to that of p alpha-1-AT. Rhesus monkeys were infused intravenously with 120 mg/kg of r alpha-1-AT (n = 13) or p alpha-1-AT (n = 12) and the serum, urine, and lung epithelial lining fluid (ELF) concentrations of these molecules quantified at various intervals.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1982

Nucleotide sequence of the triose phosphate isomerase gene of Saccharomyces cerevisiae.

The gene coding for the glycolytic enzyme triose phosphate isomerase (TPI1) was isolated from a yeast library in the shuttle vector pYE13. Selecting for a deletion mutant of the plasmid which enhances expression of the otherwise dormant yeast gene in E. coli facilitated the identification of the coding region. The DNA sequences of the wild type and mutant genes were determined by chemical methods. The 5' flanking region of the wild-type TPI1 resembles the analogous regions of the yeast genes coding for two other glycolytic enzymes. The sequence of the deletion mutant indicates that, upstream from -65 in the 5' flanking region, 3.3 kilobases have been lost from entirely within the yeast insert. The mutation reduces enzyme activity by tenfold in yeast, and its implications for the expression of the gene in yeast and E. coli are discussed. The amino acid sequence deduced from the nucleotide order is consistent with the electron density map of the protein as well as the sequence of its N-terminal 16 amino acids and amino acid composition. The amino acid sequence is approximately 50% homologous with the triose phosphate isomerases from rabbit, chicken, and coelacanth and 37% homologous with the Bacillus stearothermophilus enzyme. Residues which are thought to be catalytically important are conserved.

Amino Acid Sequence↗